Process of treating aluminum skimmings-screenings, slags, or analogous materials.



PAUL R. HERSMAN, or MILWAUKEE, wIsooNsIN, AssIsNoR,BY MESNE ASSIGNMENTS,

TO WILLIAM F. JOBBINS, INCORPORATED, OF AURORA, ILLINOIS, A CORPORATION OF ILLINOIS.

rnoonss or TREATING ALUMINUM No Drawing.

To all whom it may concern:

Be it known that I, PAUL R. HERsMAN, a subject of the Emperor of Austria-Hungary, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Processes of Treating Aluminum Skimmings, Screenings, Slags, or Analogous Materials, of which the following is a full, clear, concise, and exact description.

This invention relates to a process of treating aluminum skimmings, screenings, slags or analogous materials for the purpose of producing certain valuable and useful products.

In carrying out my invention I prefer the following procedure: The skimmings are first separated by suitable means from the larger pieces of metal occurring with them. The residual skimmings consisting of aluminum, aluminum alloys and carbid, nitrid, oxid, carbonate and other compounds of aluminum, small quantities of iron and copper and their. compounds, together with other compounds, are thoroughly washed with water, and the water separated from the undissolved portion of the skimmings by sedimentation, centrifuging or other suitable means. The solid portion is treated with a small quantity of hot dilute (approximately 39 sulfuric acid for the purpose of removing the bulk of the iron WlthOllt.

dissolving more than minimal quantities of aluminum and the solution thus formed is copper or its compounds thus precipitated separated by suitable means from the residual solids. These solids are then treated with an excess of strong sulfuric acid and the excess of acid subsequently neutralized by the addition of an excess of washed skimmings, partially purified from iron. From may be utilized as such, or may be transformed into salts of copper by well known methods. The small amount of iron in the solution may be separated by well known sKIMMINGs, SCREENINGS, SLAGS, on ANALOGOUS MATERIALS.

Specification of Letters Patent. Patented Mar; 21, 11916,

Applicationfiled Novembef 14, 1912. Serial No. 731,346. I

precipitation methods. The purified sulfate of aluminum liquor is then evaporated to such density that upon cooling it crystal-J lizes to form aluminum sulfate.

It is of course understood that various changes may be made in the procedure here discribed without departing from the spirit of the invention as set forth in the appended claims, as, for example, by making the procor analogous materials for the production of aluminum sulfate, which consists in treating with dilute sulfuric acid to remove the bulk of the iron contained in the material and subsequently dissolving the solid residue in excess of strong sulfuric acid.

2. The herein described process of treat ing aluminum skimmings, screenings, slags and analogous materials for the production.

of aluminum sulfate, which consists in treating the material with'dilute acid to remove iron, then dissolving the solid residue in excess of strong sulfuric acid and neutralizipg the excess of acid by means of skimmings partially purified from iron.

3. The herein described process of treating aluminum skimmings, screenings, slags and analogous materials for the production of aluminum sulfate, which consists in treating the material with dilute sulfuric acid to remove the bulk ofthe iron and then dissolving the solid residue in excess of strong sulfuric acid, neutralizing the excess of acid and precipitating copper by the addition of aluminum containing material.

4. The herein described process of treating aluminum skimmings, screenings, slags or analogous materials for the production of aluminum sulfate which consists in first washing the skimmings, separating the water and dissolved salts, then treating with diluted sulfuric acid to remove the bulk of the iron, subsequently dissol ing the solid residue in excess of strong sulfuric acid and neutralizing the excess of acid by an excess of skimmings partially purified from iron.

5. The herein described process of treat- 1ng aluminum skimmmgs, screenings, slags or analogous materials for the productlon of aluminum sulfate which consists in first.

washing the skimmings, separating the water and dissolved salts, then treating with diluted-sulfuric acid to remove the bulk of the iron, subsequently dissolving the solid residue in strong sulfuric acid, neutralizing the excess of acid by an excess of skimmings partially purified from iron, then purifying the resulting solution from copper by iron, and then evaporating and crystallizing the thus formedaluminum sulfate liquor to produce aluminum sulfate in solid form.

.7. The method of treating aluminum skimmings, screenings, slags, or analogous materials which consists in washing the skimmings, treating the washed skimmings with excess of acid, then neutralizing the excess of acid with excess of skimmings, and then treating the thus formed solution with metallic aluminum to precipitate copper.

8. The method of treating aluminum skimmings, screenings, slags or analogous materials, which consists in washing the skimmings, treating the washed skimmings with excess of acid, then neutralizing the excess of acid with excess of skimmings, and then treating the thus formed solution with a metal or metals of higher electrolytic solution tension than copper to precipitate the copper.

9. The method of treating aluminum skimmings, screenings, slags or analogous materials, which consists in Washing the skimmings, treating the washed, skimmings with excess of acid, then neutralizing the excess of acid with excess of skimmings, and treating the thus formed solution with reagents for the precipitation of copper or its compounds. p

10. The method of treating aluminum skimmings, screenings, slags or analogous materials to produce aluminum salts and copper, which consists in washing the skimmings, treating the washed skimmings with excess of acid, then neutralizing the excess of acid with excess of skimmings, treating the thus formed solution with a metal or metals of higher electrolytic solution tension than copper to precipitate the copper, and evaporating and crystallizing the aluminum sulfate solution to produce aluminum sulfate in solid form.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

DR. PAUL R. HERSMAN. Witnesses:

JAMES W.- LAURIE, JNo. R. MAC GREGOR. 

